Lens flare always likely to be a problem when shooting towards the light. There is flare apparent in both the non-filter and filter images. Filters are always likely to add more flare and a lens hood (as stated above) will reduce flare. When shooting into the light I always use a hood and as little glass as possible ( yes - even take that UV/skylight off!).

A lens hood is just something you put on the front of your lens that shades the lens from lights out of the frame of the shot that can cause flare like this. Its effect is like pulling down the visor shade thing in your car to shield your eyes when you're driving into the sun. Since light coming at an angle can reflect around in the lens, it can cause lens flare like you have here. A lens hood blocks any light sources from the lens that are not actually in the shot, so you reduce the likelihood of this happening.
Here's a nice detailed page about them:http://www.vanwalree.com/optics/lenshood.html